Conversion Tool

http://convert.francepropertyshop.com/
This cool looking conversion tool supports just three measurements – Length, Temperature, and Weight. But if you are looking to equalize how the Americans say it as against the British, this simple tool should do the job quickly. Put in the figure, select the unit and out pops the equivalent measurement on the other scale.

Convert World

http://www.convertworld.com/
Convertworld.com ratchets up with a few more options like wind speed conversion, absorbed dose tool, TV & monitor size converter, and a ‘language’ conversion tool, among a lot of other scientific options. You can view the converters by selecting from your choice of 28 languages.

Convert Center

http://www.convertcenter.com/
Engineering students and others too can make use of the variety of conversion options on this site. Molar mass unit conversions or frequency wavelength unit conversions will appeal to the scientifically minded. I am more interested in finding out how many gallons I can get to the liter with the fuel conversion tool.

Converticious

http://converticious.com/
The free online converter handles temperature, volume, distance, weight, area, data, time, and speed unit conversions. The interface is very user-friendly with large icons and bulleted units which you can select for your instant conversion needs.

Sooeet!

http://www.sooeet.com/
It is an offbeat name for an all-in-one unit converter. The free online tool covers all the common conversions you might use in your daily life; some purely mathematical and others (clothing size, cooking) for functional. Exchange rate calculators again are one useful tool that gives you the currency conversions with a fair degree of real time accuracy.

Metric Conversions

http://www.metric-conversions.org/
Easy to use metric conversion charts and calculators for metric conversions.